Spray head



F. WAHLIIN v SPRAY HEAD June 5, 1934.

Filed May 28,: 1932 Patented June 5, 1934 UNITED STATES SPRAY HEAD FritzWahlin, Chicago, Ill., assignor to Binks Manufacturing Company, Chicago,Ill., a corporation of Delaware Application May 28, 1932, Serial No.614,119

4 Claims.

My invention relates to a spray nozzle or spray head for projectingliquid upwardly in the form of a hollow conical spray, such spray headsbeing commonly, employed for spraying 5 water of condensation aboveponds in order that the air commingling with the finely divided spraywill cool the water.

Generally speaking, the objects of my invention are those of providing asimple and inexpensive spray head of this class which will be eiiicientin affording a wide projection and fine atomization of the spray, whichcan easily be manufactured without requiring specially designed tools ormachinery, and which will be nonclogging.

Spray heads of this class generally depend upon the upward projecting ofliquid in the form of a tube of liquid which rotating at a sufilcientrate about its own axis so that centrifugal force will initially flarethe emitted liquid tube to a thinner walled conical form, and thereafterwill cause this conical tube to rupture into tendrils which in turn aresevered into drops and then atomized into more minute droplets by theaction of the air.

In practice, it is highly desirable that both the converting of theadmitted solid stream of liquid into an upright tubular stream and theimparting of a spirally advancing movement to this tubular stream ofliquid be secured without requiring posts, vanes or other interiorformations within the spray, for these reasons:

First, because every such interior formation retards the velocity atwhich the liquid moves within the spray head, thereby reducing thespray-producing capacity of the device in proportion to its size andalso reducing the degree of atomization of the liquid when the latter issupplied at a relatively low pressure.

Second, because of the difficulty and expense in machining or otherwisemanufacturing such interior posts, spiral vanes or other formations withsufllcient accuracy for their intended purposes.

And third, because every such interior vane, partition, post or the likeforms an obstruction which will easily cause the spray head to clog incase the liquid supplied to it, has not first been carefully strained.

In my copending application #614,120 on a Hollow-cone spray nozzle, asfiled May 28, 1932, I have disclosed a single-piece spray head free fromsuch objectionable interior formations and yet designed so as. to behighly efficient both as to the liquid-projecting capacity in proportionto its size, as to the degree of atomization, and as to a maintaining ofthe -fine atomization with wide ranges in the pressure at which theliquid is supplied.

However, the spray head of this copending 60 application depends for itseificiency partly on the accuracy with which the interior of a whirlingchamber can be cored out, and on a proper machining of the part of thechamber top wall adjacent to the outlet of the device. tice, thisaccuracy can be secured to an adequate degree with ordinary brassfoundry coring and machining for spray heads of large sizes, as forexample those designed for connection to water supply pipes of over oneinch bore size, since the efiect of irregularities due to the coring ofcastings is relatively small in such large spray heads.

Such roughnesses are apt to be particularly serious when they occur onthe riser wall of the whirling chamber, because protuberances or thelike when caused on this wall will deflect petty portions of the liquidinwardly. This causes an irregular intermingling of parts of the liquidwithin this chamber and spoiling the in tended uniform wall thickness ofthe issuing tubular stream of liquid so that part of this stream willrupture into fragments of such a size as not to become properlyatomized.

My present invention aims to overcome the 35 just recited difiiculties,which have been particularly noticeable in spray heads having whirlingchambers of spiral contour, by providing a spray head consisting of twoparts, each of which can easily be machined on a lathe and arranged soas to project a uniform and finely atomized spray without requiring aspiral contour for any portion of these parts. Moreover, my inventionaims to provide a two-part construction for this purpose which willinsure a correct assembling of the parts by merely thread-- ing onethereof into the other, without requiring any particular relativerotational adjustment of these parts, and which will readily permit eachof the parts to be a drop forging of far greater durability than anyordinary casting.

In a still further aspect, my invention aims to provide a spray deviceof this class which will effect an efilcient hollow cone spray in afinely and uniformly atomized condition while employing a whirlingchamber of circular section. Heretofore, spray devices of this typeusually have included whirling chambers with spirally formed riser wallswhich are diflicult to manufacture accurately; or else have In prac- 65had these chambers relatively tall in proportion to their height,thereby projecting a poorly atomized spray and also rendering thedevices inefficient when supplied with liquid at low pressures.

Generally speaking, my present invention is based on a long series ofexperiments with various types of spray devices designed for an upwardprojection of a hollow conical spray. These experiments havedemonstrated that with a suitable displacement of the outlet fromtheaxis of the chamber in which the liquid whirls, and with a particularrelative disposition and size as well as shape of the inlet to thischamber, a highly uniform atomization of the liquid can be obtained evenwhen the chamber has an entirely cylindrical riser wall.

In addition, my experiments have shown that with flat and parallel upperand lower chamber walls and with certain proportions of various parts,such a spray device will operate eflieiently even with wide -variationsin the pressure at which the liquid is supplied.

Illustrative of my invention,

Fig. 1 is a side elevation of a spray head embodying the same.

Fig. 2 is a plan view of the same.

Fig. 3 is an enlarged side elevation of the same 'spray head, partlysectioned along the line 3.3 of Fig. 2.

Fig. 4 is a similarly enlarged plan view of the body member of the samespray head.

Fig. 5 is a fragmentary horizontal section taken along the line 55 ofFig. 3.

Fig. 6 is a fragmentary vertical section taken along the line 66 of Fig4.

Fig. '7 is a view allied to Fig. 3 but showing an embodiment of myinvention in which the tubular outlet is integral with the inlet nippleand the riser wall of the whirling chamber.

In the embodiment of Figs. 1 to 6, the body member of my spray headcomprises an upwardly open cup-like casing 1 having the lower portionsof its interior formed to afiord, a whirling chamber which has a fiatand horizontal bottom 2 and a cylindrical riser wall 3, the axis A ofwhich wall is at rightangles to the said chamber bottom; and the bodymember-also includes an inlet nipple 4, the bore of which opens into thewhirling chamber tangentially of the cylindrical chamber wall 3.

The upper portion of the casing part 1 is bored out and tapped to afforda screw thread 6 of larger diameter than that of the chamber Wall 3, theaxis 0 of this screw thread-being parallel to the chamber wall axis Abut ofiset from the latter axis as hereafter recited. Threaded into thescrew thread 6 and preferably bottoming on an annular shoulder '7 (asshown in Fig. 3) is the lower portion 8 of a cap provided with an axialbore 9 which forms the outlet of the whirling chamber.

With the two parts of my spray head thus constructed and assembled, theliquid, admitted under pressure through the inlet 4, swirls aroundwithin the cylindrically walled whirling chamber 3 and thereafteradvances spirally toward within the outlet bore 9, and centrifugalaction keeps the liquid away from the axis of the outlet so that thecross section of the liquid may be as shown in dotted lines at 10 inFig; 3. As soon as the tubular spiraling stream of liquid issues fromthe outlet bore, centrifugal action flares it out into a hollow conewhich ruptures into liquid figments and thereafter is atomized.

By constructing my spray head of a body member which includes a whirlingcasing and an inlet nipple integral with that casing, and a separatelyattached cap, I permit both the bottom and the inner riser wall of thiscasing to be machined cheaply and accurately before the cap is attached.So also, both the lower end face 8A and the bore 9 of the cap can beaccurately and smoothly machined, and the several portions of the boreof the nipple can be cheaply and accurately bored out.

Consequently, I entirely avoid the pitting, protuberanees and otherinterior surface irregularities which will occur in a single piece sprayhead of this type when its interior is cored, and which irregularitiesinterfere with the efficiency of the spray head to an increasing extentas the size of the spray head is decreased. In addition, thedetachability of the cap, which preferably has its head portion ofpolygonal shape so as to be easily gripped by a wrench, permits speedyaccess to the interior of the casing for cleaning it when necessary, andthe simplicity of both parts permits each of them -ber-namely thedistance between the fiat chamber bottom 2 and the bottom of the cap 8-should be approximately equal to, but not materially greater than, theradius of the riser wall 3 of the said chamber.

2. The diameter of theinward portion 11A of the bore of the inlet.shouldbe approximately five-eighths the interior diameter of the liquid supplypipe 12 attached to the nipple, the threads of the nipple for receivingthis pipe should be coaxial with the said inward bore portion 11A, andthe interposed bore portionllB should be conical.

3. The spacings of the axis A of the riser wall of the whirling chamberfrom the axis 13 of the nipple bore, in a plane at right angles to theaxis A, should be approximately equal to the difference between theradii of the said wall and the inner part 11A of the nipple bore. v

4. The spacingT between the axis of the riser wall 3 and the axis of thethreaded casing bore portion 6 should be approximately two-thirds theradius of the outlet bore 9 in the cap, and the diameter of this outletbore should be approximately equal to but not greater than, the diameterof the inner inlet bore portion 11A.

5. The axis A of the riser wall 3 and the axis 0 of the eccentricallybored upper portion of 140 the casing should both be in a commonvertical plane P extending at an angle 14 of about 30 with respect tothe axis 13 of the inlet bore, with the saidaxis O offset from the axisA in a direction away from the apex of the said 145 angle.

'6. The length (or height) of the outlet "ore 9 should be at least equalto and desirably about one-sixth greater than its diameter.

7. The juncture of the bottom face 8A with 150 the outlet bore 9 shouldbe sharply right-angled in all sections diametric of this bore.

8. The inner height of the whirling chamber should be somewhat greaterthan the diameter of the inward inlet bore portion 11A; and the shorterside of that inlet bore portionshould be of a length at least equal toits radius.

9. The elevation of the upper end wall (8A in Fig. 3) of the whirlingchamber above the top of the inlet bore 11A should be a. minor fractionof the radius of the said inlet bore. for the reason that the incomingand initially cylindrical stream of liquid has its direct effect mainlyon the liquid in the chamber which is at the height corresponding to thevertical spread of the inlet bore. Consequently, the liquid at higherelevation than the top of this horizontal inlet bore will be more freeto shift so as to have its vertical bore (namely the corresponding partof the dotted line 9 in Fig. 3) axial of the cylindrical chamber.However, with the said elevation of the top of the chamber only slightlyaboye that of the top of the inlet bore, this shifting tendency isimmaterial. 10. The elevation of the lowermost portion of the inlet bore11A above the bottom of the chamber likewise should be a minor fractionof the diameter of the said bore, and in practice desirably is justsufficient to afford ample clearance for the drill or reamer which boresor smooths the said bore, so that the diameter of the inlet bore shouldbe at least approximately seven-eighths of the height of the inletchamber.

With my spray head thus proportioned, the stream of water admittedthrough a supply pipe 12 attached to the nipple 4 is first contracted toa smaller diametered cylindrical stream within the inlet bore portion11A and then admitted to the whirling chamber adjacent to the riser wall3 of that chamber, and the admitted stream spreads along that wall to asomewhat greater height than the diameter of the entering stream. Thisprovis'on for an initial upward and downward spreading of the admittedliquid and the subsequent whirling of the stream within the cylindricalchamber without a further increase in its height have been found toproduce an effect allied to that of whirling a liquid stream within aspiral chamber which decreases in radius in the direction in which thestream whirls.

That is to say, the action is as if the chamber wall were curved aboutthe axis 0 as a spiraling axis, so that I am able to secure theadvantages of such a spiral'ng without encountering the manufacturingdifficulties involved in machining a spiraled wall. Indeed, I have foundthat with my easily and cheaply manufactured twopart spray heads madefor use with water supply pipes ranging all the way from one-fourth inchto one and one-quarter inch bores, I can efficiently produce hollowconical sprays of far more uniform atomization than those heretoforeobtained with commercial spray heads employed for the same pipe sizes,and also have found that my here presented spray head will functioneffectively with considerable variations in the pressure at which thewater is supplied.

However, while I have heretofore described my invention in an embodimentin which the outlet is formed in a spray head part detachable from thepart which includes both the inlet nipple and the cylindrical riser wallof the chamber, I do not wish to be limited in this "threadedlyconnected parts;

13 are integral with the riser wall of the chamber and the inlet nipple1, and in which the eccentrically disposed thread 6 extends upwardlyinto the body member. In this case, the flat top of the detachable part14 forms the bottom of the whirlng chamber and abuts upwardly againstthe annular shoulder '7 on the body member. With this embodiment, thelower face of the detachable part 14 desirably is flat and at rightangles to the axis of that part, so that when placed on a floor 15 itwill support the spray head with the outlet axis upright.

With each of the illustrated embodiments, it will be noted that I employno posts, partitions or riser vanes within the whirling chamber as hasheretofore been customary with spray heads of this class, therebyavoiding all tendency toward a clogging of the spray head by nonliquidmaterials carried into it or which might drop into it when the sprayhead is not in use. Moreover, since the detachable part can easily beunscrewed, the user has convenient access to all interior parts,which'could not be obtained in a single-piece spray head.

However, while I have heretofore described my spray head as positionedfor the upward projecting of a hollow conical spray, I do not wish to belimited in this respect, since it obviously might be inverted or tiltedif desired. Nor do I wish to be limitedto the above described details ofconstruction and arrangement, since changes might obviously be madewithout de-' ,heads for use filth a water pipe of one-quarter inch bore;that is to say, an upward taper of no more than about two degrees mightbe employed,

although too small to illustrate on the scaleof the present drawing.

In the claims, it is to be understood that the term cylindricalasdescribing the shape of the riser wall of the whirling chamber is usedin its generally accepted meaning of indicating that this wall has auniform circular section.

I claim as my invention:

1. A spray head for projecting liquid in the t form of an upwardlywidening conical spray from a whirling chamber, comprising two one partbeing formed to afford having an upright cylindrical riser wall and ahorizontal top wall of the chamber, and the other part afiording ahorizontal lower end wall of the chamber; .one of the parts including aninlet nipple disposed with the axis of the nipple horizontal and withthe bore of the nipple opening into the said chamb through a circularchamber inlet tangentiai the said riser wall, and the upper oi t partshaving an outlet of cylindricalhoz upward from the interior of the saidvial"? th axis c. the said outlet being displaced I the axis of the saidriser wall both away from the riser wall portion to which the inlet istangential, and in a direction opposite to that of the liquid enteringthe chamber through th inlet.

2. A spray head for projecting liquid in the form of an upwardlywidening conical spray, comprising a hollow and rigid body formed toalford an upright interior circular-cylindrical whirling chamber havinga circular horizontal section, and having horizontal top and bottomwalls, a horizontal inlet bore of circular section leading to the saidchamber tangential to the riser wall of the said chamber, and an uprightoutlet bore leading from the top of the said chamber; the diameter ofthe inlet bore and the outlet bore being each approximately seveneighthsof the height of the said chamber; and the axis of the said outlet borebeing offset from the axis of the said riser wall both away from theriser wall portion to which the inlet is tangential, and in a directionopposite to the direction in which the liquid enters the chamber throughthe said inlet; the said inlet bore being freely spaced both upwardlyand downwardly from the said top and bottom walls of the whirling-chamber.

3. A spray head for projecting liquid upwardly in the form of anupwardly widening conical spray from a whirling chamber, comprising twothreadedly connected rigid body parts; one part being formed to affordhaving a recess having an upright circular-cylindrical riser wall and aI horizontal end wall, and the other part affording displaced from theaxis of the said riser wall both away frim the riser wall portion towhich the inlet is tangential, and in a direction opposite to that ofthe liquid entering the chamber through the inlet; the bore of theoutlet and that of the said inlet being equal, and the horizontalchamber end wall afforded by the upper of the said two body parts beingspaced upwardly from the uppermost portion of the said inlet by adistance which is a minor fraction of the radius of the said inlet.

4. A two-part spray head for projecting liquid in the form of anupwardly widening hollow conical spray, comprising a body member formedto provide aninterior upright and circular-cylindrical recess having ahorizontal end wall; the body member having at its other vertical end anupright threaded bore of larger diameter than the said chamber and intowhich the recess opens; and having a horizontal inlet bore of circularcross-section leading to the said recess tangential to the cylindricalriser wall of the recess; and a rigid cap member'threaded into the saidbore and affording a second horizontal end wall for the said recess; themember affording the upper of the said walls having an axial and uprightcylindrical outlet of equal diameter with the said inlet bore extendingupwardly from and.

integral with the lastnamed wall; theaxis of the said threaded boredisplaced from the axis of the said riser wall of the chamber both awayfrom the portion of the riser wall to which the inlet is tangential, andin a direction opposite to that of the liquid entering the chamberthrough the inlet; the body member and the cap member havinginterengaging formations for positively limiting the threadedinterconnecting of the said two members so as to space the said endwalls by a distance approximately one-seventh greater than the saidequal diameters of the inlet and the outlet.

FRITZ WAHLIN.

